Sheath forming apparatus



Sept. 25, 1956 E. w. REYNOLDS ETAL 2,764,214 SHEATH FORMING APPARATUS Filed Sept. 11, 1952 8 Sheets-Sheet l INVENTORS [I W REYNOLDS H. C. SLECHTA B! AfTbRA/E l 25, 1956 E. w. REYNOLDS ET AL 2,764,214

SHEATH FORMING APPARATUS 8 Sheets-Sheet 2 Filed Sept. 11, 1952 FIG 2 lNVENTO/PS E. n. REYNOLDS 8,17. C. SLECHTA ATTQRNEV p -5, 1956 E. w. REYNOLDS ETAL 2,764,214

SHEATH FORMING APPARATUS 8 Sheets-Sheet 3 Filed. Sept. 11, 1952 FIG 3 m M y Gym M W E R RL 0 v 5 H H Sept. 1956 E. w. REYNOLDS ETAL 2,764,214

SHEATH FORMING APPARATUS Filed Sept. 11, 1952 8 Sheets-Sheet 4 lNl/ENTORS E. W. REYNOLDS H. C. 5 LE CH TA MIA/MASK AT-TO'PNE/ p 5, 1956 E. w. REYNOLDS ET AL 2,764,214

SHEATH FORMING APPARATUS Filed Sept. 11, 1952 8 Sheets-Sheet 5 /Nl/ENTOP$ E. W REYNOLDS 5115/, C; SLECHTA Sept. 25, 1956 E. w. REYNOLDS ET L 2,764,214

SHEATH FORMING APPARATUS Filed Sept. 11, 1952 I 8 Sheets-Sheet 6 //Vl/ENTOR$ E. W REYNOLDS H. C. SLE CH TA ATTORNEY Sept. 25, 1956 E. w. REYNOLDS ET AL 2,764,214

SHEATH FORMING APPARATUS Filed Sept. 11, 1952 8 Sheets-Sheet 7 lNVENTORS E PK REYNOLDS H C. SLE Ch TA .4 T'TO'R NE 1 P 25, 1956 E. w. REYNOLDS ETAL 2,764,214

SHEATH FORMING APPARATUS 8 Sheets-Sheet 8 Filed Sept. 11, 1952 Illl Il l

United States Patent SHEATH FORMING APPARATUS Ellwood W. Reynolds, Watchuug, and Henry C. Slechta,

Plainfield, N. J., assignors to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application September 11, 1952, Serial No. 308,962

6 Claims. (Cl. 153-32) This invention relates to cable forming apparatus and more particularly to apparatus for forming metal tapes longitudinally about cable cores.

In the manufacture of certain types of cables for use in the telephone industry, metal sheaths are formed about a cable core composed of a plurality of insulated electrical conductors. The sheaths formed from metal tape, laterally corrugated for large cables, have been bent longitudinally about cable cores utilizing the cable core as a forming mandrel. In some instances, this has proven undesirable, first, due to the very large compressive forces required to bend the sheath to circular form may crush the insulation on the core and second, even slight var-iations in the core diameter along its length may cause mismatching of the corrugations at the overlap or buckling of the edges of a flat metal tape. The cores, when composed of one or a plurality of groups of insulated conductors, have one or more servings of paper tape as a protective covering, but this protective covering is not always suflicient to withstand the forces required when the cable core acts as a mandrel for the bending of a metal sheath thereon, particularly when the metal sheath is of relatively stiff material such as steel.

The object of the present invention is an apparatus in a cable forming machine which is simple in structure and highly efficient for forming a metal sheath on acable core.

With this and other objects in View, the invention comprises units mounted at spaced positions about the path of the core and having guided rollers movably carried thereby to jointly cooperate in bending a metal tape about the core while other means are provided to move the units relative to the path of the core whereby the guide rollers will be moved simultaneously relative to the core to position them for bending tapes of various widths about cores of various sizes.

The present embodiment of the invention also includes a tubular mandrel about which the tape may be bent free of engagement with the core after which companion rollers of a forming unit assure circular formation of the tape about the core and the edges of the tape spaced from each other before entering a lapping die where the edges are guided into overlapping positions while the sheath is closed about the core. The final feature of the invention includes a die which includes spring pressed shoes to set the metal of the sheath.

Other objects and advantages will be apparent from the following detailed description when considered in conjunction with the accompanying drawings, wherein:

Fig. l is a side elevational view of the apparatus;

Fig. 2 is a front elevational view of the first of a plurality of forming units;

Fig. 3 is a front elevational view of the fifth forming unit;

Fig. 4 is a front elevational view of the sixth forming unit;

Fig. 5 is a front elevational view of the eighth forming Unit,

Fig. 6 is a fragmentary isometric view of a portion of the belt driving means;

Fig. 7 is a fragmentary side elevational view of a portion of one of the forming units illustrating the control means therefor;

Fig. 8 is a front elevational view of another forming unit positioned beyond the series of forming units;

Fig. 9 is an isometric vertical sectional view of the Lapping die disposed beyond the forming unit shown in Figs. 10 and 11 are isometric views of the edge controlling element of the lapping die, and

Fig. 12 is a vertical sectional view of the setting die.

Referring now to the drawings, attention is first directed to Fig. l which illustrates the apparatus as comprising a main frame or base 15 disposed relative to the path of a longitudinally movable cable core 16. The apparatus includes a series of forming units 21, 22, 23, 24, 25, 26, 27, 28, 29 and 30, which are very similar in structure, their differences lying in the positions of guide rollers which assist in bending a tape 32 longitudinally about the core. In the present embodiment of the invention, a mandrel 33 in the form of a metal tube having an inner diameter adapted to receive and accurately guide the cable core 16 in its given path, and an outer diameter only of sufiicient dimensions to assure rigidity of the man drel and permit bending of the tape thereon. The mandrel 33 is supported at 34 adjacent its entrance and while the remaining portions of the mandrel are supported by certain of the guide rollers of the units 21 to 30, inclusive.

The units 21 to inclusive, have vertical supports 36 disposed like distances apart, mounted on the main frame 15 and connected by members 37 to form a rigid structure. The vertical supports 36 are substantially identical in structure they having apertures 40 near their upper ends substantially concentric with the path of the cable core and varying in certain instances, as may be seen by comparing Fig. 2 with Figs. 3, 4, and 5, to accommodate the various units. One of the main portions of each unit is the movable or rocking element 41 which is of an annular contour supported by grooved blocks 42 carried by its vertical support 36. Certain of the grooved blocks may have locking means as indicated at 43 to hold the unit or the element 41 thereof in any selected position. Associated with the elements 41 are plain guide rollers 44 and grooved guide rollers 45. The rollers 44 and 45 are rotatably supported by arms 46 which are substantially identical in structure although some may be identified as left arms While others may be identified as right arms. The arms 46 are of the contour shown particularly in Fig. 2, provided with recessed elongate apertures 47 to cooperate with a headed pin 48 carried by its vertical support 36 while an elongate slot 49 in the arm cooperates with a pin 50 also carried by the vertical support 36, to cooperate with the pin 48 to guide the arm in a given path whereby its roller 4-. 45 may move radially relative to the center line of the core 16 and the element 41. The arm 46 carries a pin-like projection 52 disposed in radial alignment with its roller 44-45 and receivable in an arcuate cam-like aperture 53 of its element 41 whereby rocking movement of the element 41 in one direction or the other will result in the cam 53 moving the pin 52 and with it, the arm 46 and its roller 44-45 toward or away from the center line of the cable core. With the arms 46 in all the units 21 to 30 inclusive, substantially identical in structure and other accuracies being considered in the locations of the pins 52 and the arcuate cams 53, like rocking movements of the elements 41 will impart like movements to all of .the arms 46. By viewing Figs. 2 to 5 inclusive, it will be noted that the number of guide rollers 44-45 and sup porting arms 46 may vary in number. In all positions and in all units 21 to 30 inclusive, there are two grooved rollers 45 due to the fact that two endless belts 55 and 56 travel over the grooved rollers and cooperate therewith in forming the metal tape 32 about the mandrel 33. The variation, therefore, lies in the number of plain rollers 44 employed in the units 21 to 30, inclusive. The plain rollers serve in supporting the mandrel 33 above or below its center line depending upon the positions of the belts 55 and 56 and grooved rollers and the direction of forces applied thereby to the mandrel. The plain rollers also hold the formed portions of the tape in close engagement with the mandrel.

A mechanism is provided to connect all of the units 21 to 30 inclusive, or the elements 41 thereof and to move them simultaneously any desired distance in either direction to simultaneously move the guide rollers relative to the center line of the path of the cable, whereby tapes 32 of various widths may be bent about and formed on cable cores of various sizes. In such instances, a mandrel 33 selected from mandrels of various sizes for the particular cable core to be covered, would be removably mounted at 34 in the apparatus.

The mechanism for operating the units 21 to 30 inclusive, includes a rotatable shaft 16, shown in Fig. 7, mounted for rotation in suitable bearings 61, supported by the member 36 of the unit 30 and formed at 62 at its outer end to receive a crank 63 or other suitable means whereby the shaft 60 may be rocked or rotated in either direction. A worm 64 mounted on the shaft 60, interengages a worm gear 65 which is mounted on a shaft 66.

The shaft 66 extends through the members 36 in all of connected through .the aid of turnbuckles 70 to upper rods 71. The upper rods 71 are pivotally connected at 72 to pin supporting members 73 mounted at like positions on the rocking elements 41 of their respective units 21 to 30 inclusive. The turnbuckle 70 in each instance acts as a means for initially setting its respective unit or rocking element 41, after which, all of the units will be operativ'ely connected to each other and primarily connected to the actuating means shown in Fig. 7, whereby like motions may be imparted to the rocking elements 41 to move the roller supporting arms and their guide rollers like distances relative to the path of the cable core.

The endless belts 55 and 56 are driven by a motor 75 (Fig. 1) through a speed reducing unit 76. The output shaft 77 of the unit 76 is operatively connected to a shaft 78 by a sprocket and chain connection 79. A grooved drive roller 80 mounted on the shaft 78 receives the belts 55 and 56 at spaced positions and causes the belts to travel in the directions of the arrows. Other rollers 81, 82, 83 and 84 are mounted on their respective and is therefore held at a fixed position relative to the center line of the core, while the roller 91 is rotatably supported by a yoke 96 resting against the circular member 39 and movable vertically in a stationary guide 97 but normally urged downwardly toward the roller 90 by force established in a spring 98. The force in the spring 98 may be varied by an adjusting screw 99. Headed pins 100 and their companion elongate apertures 101 assist in connecting the yoke 96 to the member 97 for guiding movement of the yoke. The roller 91 is substantially identical to the roller 90 with the exception of the annular retaining flange 102 at the center thereof to ride between the edges of the tape, forming the sheath about the core to hold them spaced from each other until after the sheathed cable enters the lapping die and assure proper alignment of the edges with the lapping die.

The lapping die 94 (shown in Figs. 1, 9, l0 and 11) is mounted on the back of the mounting plate 89 which is removed from the structure (shown in Fig. 9) so as to more clearly illustrate the structure of the lapping die. The lapping die 94 has a central aperture 105 which is sufficently large to receive the core 16 with the sheath 32 in the opened position with the longitudinal edges spaced from each other when leaving the rollers 90 and 91. The aperture 105 decreases in size from the entrance end of the die to the exit end thereof to bring about forcing of the tape or metal sheath closely about the core, while the lapping tool 106 controls the lapping of the edges, one over the other. The tool 106 is somewhat wedge-shaped in general contour, receivable in a notch 107 of similar contour in the die 94 and removably held in place by tapered pins 108. The tool 106 has a central portion 109 rounded at 110 at its leading end and formed to provide a shoulder 111 against which one edge of the tape 32 will be caused to engage while companion surfaces 112 and 113 control the path of the other edge of the tape. It will be noted that the surface 112 will allow its respective edge of the tape to move toward the other edge of the tape but during this movement, the tapered surface 113 will push its respective edge of the tape toward the center of the core whereby, through the combination of the surfaces 111, 112, and 113, the edges of the tape will move into overlapping positions as the contour of the die aperture 105 closes the sheath about the core.

Although the forming operations have been completed when the sheathed core leaves the lapping die 94, an additional operation is necessary to prevent the inherent resiliency of the metal tape tending to open the tape. The additional unit is shown at 115 (in Figs. 1 and 12) mounted in general on parallel rods 116 of a frame 117 mounted on the support 15 to support the carriage 118 shafts to cooperate with the drive roller 50 and the grooved rollers 45 of the various units 21 to 30 inclusive,

to control the paths of the belts, causing them to func tion in cooperation with the rollers 44 and the mandrel 33 in forming the metal tape 32 about the core.

Another unit indicated generally at 85 (Figs. 1 and 8) is mounted on a vertical member 86 carried by the support 15, both the unit and the vertical member being centrally apertured at 87 concentric with the core 16. The unit 85 is removably mounted by the aid of clamps 88, supported by the vertical member 86, and adjustable about the center line of the core. This adjustment is made possible through the circular contour of the mounting plate 89 carried by the clamps 88. Companion rollers 90 and 91 are disposed below and above the path of the cable and formed to jointly substantially surround the sheath covered core to assist in forming the sheath about the core and to guide the sheathed core to a lapping die 94. The roller 90 is rotatably supported by brackets for adjustment longitudinally of the path of the cable. The carriage 118 supports parallel rods 119 upon which a main element 120 may be adjusted vertically relative to the path of the core depending upon the size of the core being processed. The element 120 has a grooved member 121 mounted thereon to support the sheathed cable as it leaves the lapping die 94. A plurality of shoes 122 are disposed at spaced positions about the core to engage spaced portions of the sheathed core and cooperate with the member 121 in setting the metal of the sheath to prevent it from opening. The shoes 122 have parallel pins 123 and 124 interengaging supporting blocks 125 of the member 120. The pins 124 are forced inwardly toward the center of the core by the aid of springs 126, these forces being varied through the adjustment of hand screws 127.

Considering now the operation of the apparatus, let it be assumed that the core 16 and the tape 32 are threaded through the apparatus in a conventional manner and that we consider now only the continued operation of the apparatus beginning with the entrance of the cable into the mandrel 32 so that the cable is completely surrounded by the mandrel which is more uniform in contour and sufficiently durable to withstand the bending of the metal tape 32 to bring about the major formation of the sheath about the core. Referring now to units 21 and 3 inclusive, attention is first directed to unit 21 (Fig. 2) which illustrates the endless belts 55 and 56 starting to bend the metal sheath about the mandrel 33 while the rollers 44 assist in supporting the mandrel against the forces applied through the rollers 45 to the tape 32. It is not thought neces sary to show in detail all of the units 21 to 30, inclusive. In each unit there are two rollers 45 and their adjustable supporting arms 46. These grooved rollers and their supporting arms vary in their positions about the center line of the core (as illustrated in Figs. 2, 3, 4 and 5) to cause the endless belts, assisted by the grooved rollers, to bend the tape 32 about the mandrel until the sheath is in the position shown in Fig. 8. The plain rollers 44 (as illustrated in Figs. 2 to 5 inclusive) may vary in number depending upon the services they are to render in maintaining the mandrel and tape in position and depending also on the limited space adjacent the mandrel.

It is apparent that the units 21 to 30 inclusive, may be adjusted for various size of cable through the rotation of crank 63 (Fig. 7) to bring about simultaneous actuation of the levers 67, rocking the shaft 66 and the elements 41 through the connecting arms. During initial setting of the machine, the turnbuckle 70 may be actuated, but once the apparatus is set for a cable of one size, the individual adjustments of the units are not necessary, they being adjusted simultaneously to accurately position the guide rollers 44 and 45 relative to the path of the core.

It has been described how the metal sheath is formed about the mandrel 33 which has taken the abuse of the forming operations and protected the cable core until a sheath has been given a circular contour about the core where it leaves the mandrel between the unit 34) and the unit 85. The unit 85 is essential in assuring circular formation of the sheath about the core, its primary purpose being to maintain the edges of the sheath at spaced positions until after the sheathed core enters the lapping die 94. While the sheathed core travels through lapping die 94, one of the edges of the metal sheath will be caused to travel in a given path engaging the surface 111 of the tool 106 while the other edge is urged inwardly by the tapered surface 113 during the time the decreasing contour of the aperture 105 forces the metal sheath closely about the core permitting the edges to overlap as one edge moves along the surface 112. This completes the formation of the metal sheath about the core, and as it moves through the setting die 115, where the shoes 122 cooperating with the fixed member 121 set the metal of the sheath, completing the operation.

It is to be understood that the above described arrangements are simply illustrative of the application of the principles of the invention. Numerous other arrange ments may be readily devised by those skilled in the art which will embody the principles of the invention and fall within the spirit and scope thereof.

What is claimed is:

1. In an apparatus for making cable of various sizes comprising cores and sheaths thereon consisting of transversely corrugted metal tapes folded about the cores during longitudinal advancement of the cores and tapes in single sets in longitudinal paths, the apparatus comprising a base disposed with respect to the paths, supports mounted on the base at positions spaced longitudinally of the paths, units mounted on their respective supports and having elements movable about the path of the core, guide rollers movable by the elements and carried by the supports to jointly cooperate in bending a metal tape about a core, members supporting the guide rollers and connected to their respective elements whereby movement of the elements will move the guide rollers relative to the paths to position them for bending tapes of various widths about cores of various sizes, and means 6 to move the elements simultaneously to simultaneously set the guide rollers.

2. In an apparatus for making cable of various sizes comprising cores and sheaths thereon consisting of transversely corrugated metal tapes folded about the cores during longitudinal advancement of the cores and tapes in single sets in longitudinal paths, the apparatus comprising a base disposed with respect to the paths, supports mounted on the base at positions spaced longitudinally of the paths, units mounted on their respective supports and having elements adapted for rocking movement about the path of the core, guide rollers movable by the elements and carried by the supports to jointly cooperate in bending a metal tape about a core, and means to rock the elements simultaneously about the path of the core whereby the guide rollers will be moved simultaneously relative to the paths to position them for bending tapes of various Widths about cores of various slzes.

3. In an apparatus for making cable of various sizes comprising cores and sheaths thereon consisting of transversely corrugated metal tapes folded about the cores during longitudinal advancement of the cores and tapes in single sets in longitudinal paths, the apparatus comprising a base disposed with respect to the paths, supports mounted on the base at positions spaced longitudinally of the paths, units mounted on their respective supports and having elements adapted for movement about the path of the core, guide rollers movable by the elements and carried by the supports to jointly cooperate in bending a metal tape about a core, means to move the elements relative to the paths whereby the guide rollers will be moved simultaneously relative to the paths to position them for bending tapes of various widths about cores of various sizes, endless belts carried by and held in close engagement with the tape by some of the guide rollers to travel with the tape and cooperate to bend the tape about the core, and means including a torque motor tending to drive the belts at speeds faster than the linear speed of the tape.

4. In an apparatus for making cable of various sizes comprising cores and sheaths thereon consisting of transversely corrugated metal tapes folded about the cores during longitudinal advancement of the cores and tapes in single sets in longitudinal paths, the apparatus comprising a base disposed with respect to the paths, sup ports mounted on the base at positions spaced longitudinally of the paths, units mounted on their respective supports and having elements adapted for movement about the path of the core, guide rollers movable by the elements and carried by the supports to jointly cooperate in bending a metal tape about a core, a tube with an inner diameter substantially equal that of the core removably disposed to extend through the units to guide the core, and means to move the elements relative to the tube whereby the guide roillers will be moved simultaneously relative to the tube to position them for bending tapes about tubes for cores of various sizes.

5. In an apparatus for making cables comprising a core and a sheath thereon consisting of a metal tape folded about the core during longitudinal advancement of the core and tape in given paths, a die disposed concentric with the path of the core and having an inner contour decreasing in size from an entrance end to an exit end to cause the final forming of the tape with overlapping edges closely about the core, the die also having a slot therein extending longitudinally thereof from the entrance end, and an element mounted in the slot of the die and having a longitudinal tapered portion extending into the die between two surfaces of the element which lie in ditferent planes whereby the tapered portion will separate the edges of the tape entering the die and cooperate with the surfaces of the ele- 7 r ment to guide the edges of the tape into overlapping positions.

6. In an apparatus for making cables comprising a core and a sheath thereon consisting of a metal tape folded about the core during longitudinal advancement of the core and tape in given paths, a die disposed concentric with the path of the core and having an inner contour decreasing in size from an entrance end to an exit end to cause the final forming of the tape with overlapping edges closely about the core, the die also having a slot therein extending longitudinally thereof from the entrance end, an element mounted in the slot of the die and having a longitudinal tapered portion extending into the die between two surfaces of the element which lie in different planes whereby the tapered portion will separate the edges of the tape entering the die and cooperate with the surfaces of the element to guide the edges of the tape into overlapping positions, and a die disposed beyond the exit end of the forming die and having a member movable therein to engage the overlapped edges of the tape, and resilient means to cause the member to apply variable forces to the overlapped edges to press them into close engagement with each other and the core.

UNITED STATES PATENTS Tasker Jan. 17, Philips et a1. Apr. 10, McIntire June 5, Greenfield Feb. 23, Silverman Mar. 21, Norris Jan. 17, Still Mar. 20, Park Aug. 27, Walker Apr. 14, Blevins Mar. 14, Norsing May 2, Gonser Oct. 24,

FOREIGN PATENTS Great Britain Dec. 2, Germany Dec. 2, Great Britain Mar. 12, 

